Conventionally, therapy for selectively destroying only tumor cells has been known, such as boron neutron capture therapy (BNCT) using nuclear reaction between boron (10B) and low-energy neutrons.
Neutrons are roughly classified, for example, into the following categories based on energy (speed) although different categories are applied depending on fields of study.
Thermal neutron(to 0.5 eV)Epithermal neutron(0.5 eV to 10 keV)Fast neutron(10 keV to 20 MeV)
The thermal neutrons and the epithermal neutrons are used for the above-mentioned boron neutron capture therapy.